Download Genesis Advanced Technologies G2.2 User's Manual

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absolute fidelity
Owners Manual and Set-up Guide
Genesis 2.2 Loudspeaker System
Contents
SET-UP GUIDE
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PLANNING THE PLACEMENT
UNPACKING
ASSEMBLING THE ACOUSTIC SUSPENSION
THE SERVO-CONTROLLED BASS AMPLIFIER
MIDRANGE/TWEETER CONNECTIONS
CONTROL ADJUSTMENTS
SERVO-CONTROLLED BASS AMPLIFIER PROTECTION
TUNING THE SYSTEM
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BEGIN WITH THE BASS LEVEL
IMAGING AND SOUNDSTAGE
PHASE CONTROL
FURTHER ADJUSTMENTS
THE REFINEMENT STAGE
MAKE ONE CHANGE AT A TIME
DEFINING THE SOUNDSTAGE
APPROPRIATE MID-BASS/LOW-BASS BALANCE
ROOM TREATMENT
MASTERING THE REFINEMENTS OF THE SYSTEM
THE TECHNOLOGY
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DESIGN PHILOSOPHY
THE GENESIS RIBBON TWEETER
48INCH MIDRANGE RIBBON
THE SERVO-BASS ADVANTAGE
THE WOOFER TOWER
SERVO-CONTROLLED BASS AMPLIFIER
THE ACOUSTIC SUSPENSION
SPECIFICATIONS
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A Message from Genesis
Congratulations! And Thank You!
You are now the owner of one of the finest loudspeaker systems in
the world! The Genesis 2.2 is the result of technologies developed
and refined over the past 40 years in loudspeaker design.
The G2.2 loudspeaker system was created for the music lover who
knows (almost) no compromise. It is designed to reproduce music
(and film) at live listening levels with virtually no restrictions on
dynamic range, frequency response, or imaging capabilities. This is
“absolute fidelity™”, the ability to reproduce the musical event
faithfully, as was intended by the performer or filmmaker.
However, the G2.2 is not meant to reproduce music at ear-splitting
levels. If you are looking for just LOUD, this is the wrong
loudspeaker. A Ferrari and a Caterpillar may have the same price,
but they are very different vehicles and you wouldn’t use your
Ferrari to move gravel.
Please read this Owners Manual and Set-up Guide to get the
maximum enjoyment out of your purchase. Also, if you have
access to the internet, please check back at our website often. The
address is www.genesisloudspeakers.com. We will put the latest
updates, tips and tricks, and support for our owners on our website
and in our newsletter.
Please write the purchase details of your Genesis 2.2 System
here for future reference. Remember, send in your registration
card to extend the limited warranty on your loudspeakers.
Bought from: ____________________________
____________________________
Date: ___________________________________
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This page intentionally left blank
Warranty Statement and Extended Registration Card
should be placed here
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Set-up Guide
Now that you have your new Genesis 2 loudspeaker system, we
realize that you can’t wait to hook it up and start the music!
However, this is a big, complex system and we want you to set it
up correctly and more importantly, safely. So, please read this set
up guide (even if your dealer is setting it up for you!) before you
proceed.
Planning the Placement
Before you even have the loudspeakers delivered, it would be a
good idea to make a plan of where you will place them. You will
not need a huge room, but at an absolute minimum the room
needs to be 16 feet (5m) wide where the speakers will be placed.
You should have a minimum of at least 6 feet (2m) of space behind
the speakers. The listening position should be a minimum of 10
feet (3m) from the front of the midrange ribbon to allow for proper
integration of the drivers.
In a typical placement, the midrange/tweeter wings will be placed so
that the two columns of tweeters are on the inside, and between six
feet to eight feet (2m to 2.6m) apart. The woofer towers are placed
behind and outside the wings with the column of woofers about 4 feet
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from the midrange ribbons. In order to allow for sufficient space from
the sidewalls, this dictates that the optimum room is at least 19 feet
(6m) wide.
Placing the woofer towers asymmetrical but equidistance from the
midrange/tweeter wings will result in better bass integration in the
room. Keep the side of the woofer towers no less than 16 inches
from the sidewall.
The suggestions here are typical in a minimum space. With a larger
room, it is possible (and optimal) to have a layout as shown below
with the midrange, tweeters and woofers equidistant from the
listening position. Still, the woofer towers should be placed
asymmetric in the room with the distances of the woofers from the
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nearest wall being different.
As the room will greatly influence the sound of your system, finetuning adjustments in placement will be necessary. Every room will
be different, with doorways, closets, wall construction and covering,
etc. all making a significant impact on positioning.
Unpacking
The Genesis 2.2 system will arrive in a number of pieces. There
are four large wooden shipping crates, two containing the woofer
towers, two holding midrange/tweeter panels (or “wings”). There
will also be a pallet of cardboard boxes holding the acoustic
suspension system, the various modules of the servo-controlled
bass amplifier, and a box containing the various cables. (There
could also be up to three more boxes if you have the dynamic
reservoir and power supply upgrades to the servo-controlled bass
amplifier.)
To remove the contents of all the crates, you will need help. The
G2.2 loudspeaker system with crates weigh a total of 1,400 lbs.
Each woofer tower weighs over 220 lbs, and each tweeter tower
weighs over 150 lbs and they have to be lifted out of the shipping
crates. We are not liable for damage (to either the speakers or
your backs!) during unpacking and setting up.
We suggest the use of a forklift to move these
crates around, and at least four strong people to
un-box and position the loudspeakers. In order to
remove the loudspeakers from the crates, the front
and top of the crates can be removed. This is
secured with screws – remove all exposed screws
except the ones marked with blue paint – and the
top and front can be lifted away.
With the top and front of the crate removed, each
wing and tower of the loudspeaker can be carefully
lifted and slid out of the crate. Before you put the speaker up on its
feet, it will be necessary to install the acoustic suspension (next
page).
After unpacking, we strongly suggest that the crates be dismantled,
flattened and safely stored away in a cool, dry place. They will be
needed should you relocate or move. It will be expensive to custom
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build crates strong enough to transport these loudspeakers without
damage.
Assembling the Acoustic Suspension
A unique feature of the Genesis 2.2
loudspeaker system is the integration of an
acoustic suspension system for the
loudspeaker columns. This is an essential
feature of the cabinet structure – resulting in
lower coloration, better definition and rocksolid imaging.
The suspension system comprises of a
suspension frame made of 1-inch of solid
Acoustic Suspension under the
midrange/tweeter wings
cast acrylic, a set of Neoprene decoupling
shock absorbers, and a set of steel spikes.
Should you be placing the speakers on a hardwood floor or a floor
that would scratch easily, do not use “spike cups”. These defeat the
purpose of having a spike in the first place! Use a copper penny –
the weight of the speaker on the spike will create a depression in
the penny, and this point is what will efficiently transfer vibration to
the floorboards.
A couple of points to note during the assembly of the acoustic
suspension system:
1)
The triangular “hole” in the suspension frame points to the
front of the speaker (towards the listener).
2)
Do not over tighten the shock absorbers that are preinstalled on the cabinet – finger tight is sufficient. A hex-key
(or allen wrench) is supplied to tighten the bolts holding the
suspension frame to the shock absorbers. Again, do not
over tighten these bolts.
3)
The point of the spike should protrude through the
suspension frame only far enough to couple to the floor. If on
a concrete or marble floor, for example, 5mm or 1/5” is more
than sufficient. If you have your speakers on a 1/2" deep pile
carpet, then you will need to have the spike protrude about
3/4".
4)
If you need to move the loudspeaker after you have installed
the spikes, do not “walk” the speaker cabinet on the spikes –
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retract the spikes first. This will avoid causing damage to the
acoustic suspension and to your floor.
5)
If you have very light and resonant floorboards, you may
need to place a heavy slab of marble, slate, or granite under
the loudspeaker to avoid exciting the floor.
The Servo-Controlled Bass Amplifier
The included remote-controlled
modular Servo-Controlled Bass
Amplifier powers the woofer towers
of the G2. There are three modules
plus a power supply unit and
numerous supplied cables in the
standard configuration. Various
upgrades are also available for the
Servo-Controlled Bass Amplifier –
please check with your dealer.
The parts of the amplifier are:
1)
2)
3)
4)
5)
6)
7)
Genesis 2 Servo-Controlled Bass Amplifier
(with optional amplifier suspension for floor placement)
The electronic crossover and Control Module with left
and right balanced inputs and two control outputs.
A pair of Control Interface Cables (CIC): these have
7-pin Neutrik™ connectors at each end.
A pair of Servo-Bass Interconnects (SBI) with XLR
connectors at one end and a pair of banana plugs (or
optionally spades) at the other end.
Two Servo-feedback Amplifier Modules with one
control input, and two Neutrik 50-amp Speakon™
outputs.
Two pairs of Servo-Bass Cables (SBC) with Neutrik
50-amp Speakon™ plugs at each end.
A Power Supply for the Amplifier Modules with two
Neutrik™ 20-amp PowerCon™ outlets.
A pair of Power Umbilicals with a Neutrik 20-amp
Powercon plug at each end (one grey and one blue).
In the typical configuration, the Control Module, and two Servofeedback Amplifiers are placed in a stack between the
midrange/tweeter wings. The Power Supply is placed behind the
stack. The standard cables supplied will work for this configuration:
9-foot (3m) Servo-Bass Cables (SBC), two-foot (0.6m) Control
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Interface Cables (CIC) and 6-foot (2m) Servo-Bass Interconnects
(SBI). An alternative placement option is to have the Control
module in the middle, flanked by the two Servo-feedback
Amplifiers, with the Servo-feedback Amplifiers closer to the woofer
towers and the Control module between the midrange/tweeter
wings.
First, place the stack of modules between the midrange/tweeter
wings with the Control Module on the top and the whole stack on
an amplifier stand. Using the supplied CIC, link the Control Module
to the Servo-feedback Amplifiers. One amplifier module is for the
RIGHT woofer tower and the other will be for the LEFT. You can
figure out which it is by the last letter of the serial number. It does
not matter which CIC is used for right and which is used for left.
However, one is marked with a red ring and the other is marked
with a white ring for convenience.
Use the SBC to connect the woofer
towers to the woofer amplifier. Each
end of the cable is clearly marked,
AMPLIFIER or SPEAKER. It does not
matter which connector is attached to
which as long as the correct amplifier
module is used for the left and right
towers. It does not matter which SBC is
used for the left or the right; however,
one is marked with AMPLIFIER or
SPEAKER in red lettering, and the other
in white lettering.
When you connect the woofer tower outputs pay close attention to
the way the connector works. This connector is a 50 amp twist-lock
Neutrik™ Speakon™. It only goes in one way and you cannot put it
in wrong. However, you can fail to put it in all the way. Line up the
alignment pins on the connectors, push the plug in, and twist it
clockwise until the lock "clicks" in place to keep it there. By looking
carefully, it will be obvious as to how it works.
At the AMPLIFIER end of the servo-bass cable, you will find a male 1/8”
jack. The female end is on the chassis of the servo-bass amplifier
labelled GND. These jacks are used for grounding an internal shield
within the servo-bass cable. For the time being, leave this shield
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disconnected. The shield ground should be used only when
necessary.
Midrange/Tweeter Connections
Next, connect the mid/tweeter
panels to your power amplifier
using a pair of high quality
loudspeaker cables (not
supplied) to the 5-way binding
posts. We recommend using
good quality spade
connectors for this job.
There are two ways to get the
music signal from your
system to the Servo-Controlled Bass Amplifier to drive the woofers.
The first, and preferred way is to drive it using the output of the
power amplifier that is driving the midrange/ tweeter panels using
the supplied pair of Servo-Bass Interconnects.
Servo-Bass Interconnects
parallels speaker cable inputs
The Servo-Bass Interconnect will be supplied with a pair of banana
plugs at one end, and an XLR balanced male plug at the other end.
The banana plugs will plug straight into the binding posts of the G2
midrange/tweeter tower inputs when you are using speaker cables
with spade connectors. If your speaker cables use banana plugs,
we will be able to convert your SBI to spade connectors for a
nominal charge.
The XLR connector contains a specially developed internal
balancing circuit that enables the power amplifier to drive the
balanced input of the servo amplifier. Because of the extremely
high impedance of the balancing circuit, the parallel connection
places absolutely no stress on the power amplifier. Do not use any
other interconnect cable for this purpose as the high level output
from your power amplifier will blow the inputs of the Control
Module! This internal circuit also allows even fully balanced power
amplifiers* to be connected this way.
*
Do NOT use this method of connection with Class D power amplifiers that have both +ve
and –ve speaker outputs floating above ground. Some of these amplifiers have as much
as 36V on their speaker “ground”, and this will damage the Servo-Controlled Bass
Amplifier. Use the second method of connection.
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Plug the XLR end of the SBI into the Control Module and the
banana plug end into the binding posts of your midrange/tweeter
towers (preferred) or the output binding posts of your power amp.
Each end of the SBI has a grounding alligator clip on a flying green
lead. Leave this grounding clip disconnected for the time being. It
is not necessary in most instances.
The alternative method of connecting the servo-bass amplifier to
your system is to use a pair of balanced interconnects (not
supplied) from your preamplifier to the servo-bass amplifier. Your
preamplifier will need to have two sets of outputs, or you will need
to use a high-quality Y-cable (not supplied). If you use this method
of connection, your power amplifier will be driving the midrange/
tweeter towers and the servo-controlled bass amplifier will be
driven in parallel by your preamp.
As no power amplifier is “straight wire with gain”, we do not
recommend this way of driving your servo-bass amplifier. The
reason is that phase coherence and integration between the
midrange and bass is much harder to achieve.
Control Adjustments
Your servo-bass amplifier should be turned on last. As a general
rule, turn your system on starting at the source to the amplifiers,
and turn it off starting at the amplifier. Plug the woofer amplifier into
a power outlet*, and using the remote control, turn it on by pressing
the POWER button. The display shows on .
The display flashes to identify that the function that is being
adjusted. When you first press one of the volume control
buttons, the currently-set volume will flash. The next press will
move the volume up or down. Pressing and holding the button
will move the volume up or down rapidly. The volume has a range
of 0 to 100. A volume setting of 40 is nominal, and that is a good
place to start when making adjustments. In general, a lower bass
volume setting is needed in smaller rooms.
Next, adjust the phase with the buttons marked “PHS ” or “PHS ”
on the remote control. When you first press the phase up or down
*
Do NOT use any power conditioners with the Genesis Servo-Controlled Bass Amplifier.
We have found that every power conditioner that we have tried will restrict the dynamics of
the system – except the Titan by IsoTek Systems.
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button, the display will flash Ph and then the current phase setting
will be shown. The next press of the button will move the phase up
or down.
Set the phase to zero as an initial setting. (If you are not driving the
servo-bass amplifier as recommended using the output of the
power amplifier, the phase will depend on the phase shift and
group delay of your power amplifier. A typical value will be 45 to
135 degrees.)
The high-pass (HI) filter determines how low the woofers will play.
Set this initially to 24Hz until the woofers and amplifiers break in.
Then, it can be set to 18Hz. Next, adjust the low pass (LO) filter
(how high the woofer goes). Set this to 95 using the button marked
"low pass" (on the remote control).
You will notice two controls on the back of the
midrange/tweeter panel. The left hand knob is
a trim control for the rear tweeters. Turning
this control clockwise will increase the level of
the rear tweeters.
If there is not enough space behind the G2,
the tweeter control can be turned down. In
large rooms, the tweeter control can be
turned up. Use this control if you need a bit
more treble or to increase the apparent space
of the soundstage. Start with this control at
the twelve o'clock position.
The control on the right side is a three-position switch used to
adjust the midrange. Start at position two. Position one will sound
fuller in the lower midrange while position three will sound leaner
and have more upper midrange.
The less obvious effect (more obvious to some people!!) of the
midrange control is to make the soundstage sound more forward,
and change the perceived height and position of the performance.
Relative to position two, you can raise the soundstage by moving to
position three (it’s like moving your seat forwards in the concert
hall!!)
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Position two gives you a soundstage perspective of about the
middle of the concert hall. Position three is more like the orchestra
seats, and position one may be more like the circle seats.
While it is relatively easy to put the Genesis 2 loudspeaker system
into your room and system and get a reasonable sound, it is not as
easy to perfectly integrate the loudspeakers into your room, and
get great music out of it. The time you will take to do this properly
will be well worth it for the long-term enjoyment you will derive. This
fine tuning is covered later in this manual.
Servo-Controlled Bass Amplifier Protection
The servo-bass amplifier has numerous protection circuits built in to
protect both the amplifier and the woofers. If you over-drive the
amplifier, it will self-protect and you will hear clicking or thumping
sounds. If that happens, turn down the volume of your system to
protect your hearing and your speakers.
The amplifier is designed to be current-limited to 20amps – this is
more than enough to supply over 1600W transients to the woofers.
However, the servo-system in the G2 is not compression or
dynamic limited. Hence, it is possible to play the system too loud,
and damage the woofers.
Due to the efficiency of the amplification modules, they deliver
and draw current extremely quickly. Hence, you may find that a
very loud bass drum thwack will cause your lights to dim, or the
circuit breakers to trip if you do not supply enough power to your
system.
A possible solution will be to install an additional 20amp circuit in
your listening room, and purchase an additional power supply to
separate the power needs of the left and right woofer towers. Also,
a Dynamic Reservoir (developed for the Genesis Reference
Amplifier) is available as an optional upgrade. You will only need to
do this if heavy bass dims your lights.
A Word about Finish
The G2 is entirely covered in high-gloss acrylic. Acrylic was picked
for its sonic properties as well as its beauty. However, acrylic is a
soft material that can scratch easily.
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Every G2 system is delivered with a 3-stage acrylic polish system
by Novus. Do not use any other cleaners or polish on your G2
loudspeakers.
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Tuning the system
Music is the best way to begin to fine-tune your setup. We suggest
that video sources be used only after you have setup the system to
properly reproduce music. Fine-tune your system only after at least
200 hours of play. As the loudspeaker system breaks in, it will
sound better and better. Using the IsoTek Full System Enhancment
CD will shortcut the 200 hours needed.
Begin with the bass level
Start with a single vocal with simple instrumental accompaniment
because the sound of the human voice is more easily recognizable
than many instruments and is the least complex sound to deal
with.
Leave the low pass filter alone, for the moment, as it should remain
set at 95 Hz, This control will be addressed later. Turn the volume
control of the woofer amplifier up or down until the voice sounds
correct. Whatever controls you use, turn them up and down only a
little at a time. It is easy to turn it up or down too much.
Concentrate on the mid bass regions (as opposed to the very low
bass in your recording) to achieve a natural blend. The voice and
the music accompaniment should sound as if it were cut from one
cloth, not separate.
If the voice sounds “thin” or does not have enough “chest” to its
sound, turn the woofers amplifier’s volume up till it does. If you find
that turning the volume up creates too much low bass, decrease
the low pass filter control.
The low-pass control will raise or lower the frequency cutoff point of
the woofer. Turning the low pass filter up to a higher number will
extend the upper bass regions without affecting the low bass level.
Some rooms may require that you set the low-pass filter to 100Hz.
Do not be afraid to increase this control to give the sound more
body.
Next, set the woofers using more than just a voice. Select some
music that you know to have good deep bass. Using the volume
control on the servo amplifier’s remote control, set the woofers for a
natural and powerful bass sound. Use a symphonic piece of music
if you can, or use a natural bass instrument for your guide. Try to
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make it sound real. You may have to return to the vocal to make
sure you have not gone too far in one direction.
If, at this point, it does not have enough mid bass, turn the low pass
number to a higher position or, alternately, position the main
speakers closer together in order to achieve better mid bass
coupling between the main speakers. If it sounds too “fat” turn the
low pass control down or adjust the volume. At this point it is
suggested to use the low pass filter control until you get to the
refinement stage.
Imaging and Soundstage
If your vocal selection is a well-recorded audiophile CD or LP, the
performer should appear to come from behind the loudspeakers
and be at the appropriate height for a standing person. If it is not,
there are several remedies that will address this.
If the vocal appears to be larger than life, you should first check the
system volume. Is it a volume that would be appropriate for
someone actually singing in your room? If there is too much
volume the artist will appear too big and the opposite is true
for too little volume. If the volume is set correctly and the image is
still too big, toe the woofer towers in a slight amount or place
them closer together and re-listen. Repeat this process till you
have it right. If the voice is too low in height, turn the midrange
control to the next highest position and the image of the voice will
move upward slightly.
If you have the speakers only 20% away from the front wall, and
you are not getting enough front to back depth (the singer not
appearing behind the speaker enough) pull the midrange tweeter
panels away from the front wall a little bit at a time. If you do not
have them pulled far enough away, you may not have enough
front to back depth. If you get the speakers much beyond 1/3 of
the way into the room, it is unlikely that pulling them further away
is reasonable.
Find the best compromise for your room, your tastes and your
space requirements. If the speakers are too far apart you will lose
the side image and if they are too close together you will have too
small a center stage. We recommend you begin with six to seven
feet apart as measured from tweeter to tweeter. If you are not
getting proper focus on the voice, you may angle the midrange
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panels about 2 to 5 degrees towards your seating position until you
have a properly defined center image.
When properly set up very little sound should appear to come
directly from the speaker, instead, the sound stage should extend
far beyond the left and right edge of the loudspeakers and they
should have tremendous front to back depth. When the recording is
close miked (when the instrument or performer is very close to the
recording microphone) the music may appear to come directly
from the loudspeaker. This is normal. Typically, however, the
sound should appear to be detached from the loudspeakers.
A simple rule of thumb to follow is that focus will be achieved by
placing the speakers closer together or farther apart, and front to
back depth can be adjusted by the distance from the rear wall.
Further, as the system “breaks in”, the depth and width of the
soundstage will increase, and so will the “smoothness” of the
sound.
Phase Control
We suggested in the beginning of this manual to set the phase to
zero degrees. Now that you have roughed the system in, you may
want to experiment with different phase angles.
Using the remote control you can adjust the woofer's phase angle
up and down in five-degree increments.
The changes are subtle and they usually affect the imaging and
soundstage. Listen carefully to the positioning (in acoustic space)
of the orchestral players as you change the phase control. You
may notice small shifts in their apparent relationship to the other
members of the orchestra. Do not expect them to actually move.
Expect minute changes in the soundstage, the apparent width of
the stage, your ability to distinguish individual players etc. If you
reach a phase shift of ninety degrees you have probably gone too
far. Using the recommended connection, the phase shift needed is
usually below ten.
The other change to listen for is coherence and timing. Adjust the
phase will subtly change the relationship between the bass and the
midrange. When you get the phase perfectly correct, you will find that
the timing between the vocalist and the double bass “snaps” in place,
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and your foot will start to tap, and you will sway to the music. This is
basically what we term “PRAT” – or pace, rhythm and timing.
Further adjustments
With the woofer towers positioned in the recommended placement
behind and outside the midrange tweeter panels, low bass in the
room should not be a problem. Should you have too much bass,
simply turn the volume down on the remote control. Too little, and
the opposite will apply.
In general, the low-pass filter and the bass volume goes in opposite
directions. With higher bass volume, a lower frequency for the lowpass is needed. And with lower bass volume, a higher frequency is
needed for the low-pass.
In some problematic rooms a resonance may develop at one or
two frequencies that is unnatural to the music. By moving the
woofer towers closer to the rear wall or farther from the rear wall,
the resonance may be reduced at the listener’s position. There
are no absolute rules concerning problematic rooms, so do not be
afraid to experiment with best woofer placement.
Ultimately, it is all about balance. You have a number of controls
at hand with which to adjust the bass response, the low-pass filter
frequency and woofer volume. You can also move the speakers
closer together (for better coupling), and also move the woofer
towers closer together, or further apart, or even move them closer
to a corner of the room for more bass.
One trick that we have found to always work is NOT to have the
woofer towers placed symmetrically in the listening room. When
you have the woofers equidistant to the walls, there will be wallloading which will increase the volume of some frequencies in the
bass and mid-bass.
Place the left and right woofer towers equidistant from the midrange
towers. However, have one woofer tower further to the side of one
midrange tower, and have the other woofer tower further to the back
of the other midrange tower. It may look strange, but the principle
here is to position the midrange/tweeter towers for the best imaging
and soundstage, and the woofer towers for the smoothest and best
bass and ambience retrieval.
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The Refinement stage
After following the rough setup guide above, you may not be
completely satisfied with the results. We share with you here some
of our observations in setting up these loudspeakers.
Make One Change At A Time
One rule of thumb you should always keep in mind. Make one
change at a time! Do not, for instance, change position of the
speakers and make an adjustment to the amplifier all at once.
Make each of these changes separately and note the difference by listening - with each adjustment, then make the next change.
Each adjustment, in positioning, and in control adjustment will
result in a subtle sonic change. Even when you are moving the
midrange/tweeter panels further apart, or closer together, move
one panel, listen, and then move the other panel. You may also
find an asymmetric placement in-room more accurate and
pleasing.
Defining the Soundstage
A common problem we find with many set-ups is a tendency to
separate the speakers too far from each other. This gives an
unnaturally stretched soundstage between the two speakers, and
creates problems with focus. The key problem is a lack of
soundstage information beyond the left and right sides of the
speakers.
If you find that the sound is not spacious enough or you are not
getting enough front to back depth, pull the speaker away from the
front wall. This is typically preferable to separating the two
speakers too far, and will almost always give you better depth and
soundstage information. A word of caution though: if you move the
speakers too far from the front wall you may lose the focus of the
image.
A problem with the soundstage could also be caused by the
recording. Try another recording if you cannot achieve what you
are trying to do.
Appropriate Mid-bass/Low-bass Balance
Yet another problem is a lack of mid bass energy. In order for the
appropriate amount of mid bass energy to be present, the speakers
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should be close enough together to achieve proper "coupling" of the
midrange ribbon driver. Coupling is desirable in the lower
frequencies from the mid-bass on down. This simply means that the
left and right drivers "work together" as opposed to working
separately.
If you find there isn't enough deep bass, your first remedy is the
volume control on the woofer amplifier. This has several limitations.
First, turned up too high, you may get some distortion on very low
frequencies or you may overheat the amplifier.
Push the woofer towers back towards the rear wall. This will
increase the coupling of the woofers to the room. Do this procedure
in small increments (approximately three inches at a time) and
return often to the recordings you have used to adjust the front to
back depth and soundstage properties of your system. It is easy,
yet unproductive, to go too far in one direction (and if you move the
woofer towers too far from the rear wall you may lose low bass
extension).
Secondly, you may make the mid bass produced by the top of the
woofer out of proportion with the mid bass produced by the bottom
of the midrange ribbon. This would tend to sound bloated or thick in
the mid bass regions.
Another good rule of thumb is to first set the volume control of the
woofer towers for proper midbass rather than low bass. The theory
is that if the midbass is correct, then the low bass should be very
close to correct. If the midbass is proper and the low bass is still not
right, here are some other suggestions.
A good balance between proper low bass extension and a deep
and spacious soundstage needs to be established to optimize your
new speaker's performance.
In order to achieve what the speaker is capable of we suggest you
focus your efforts on a proper balance of soundstage elements that
includes information beyond the left and right sides of the
speakers, front to back depth well behind the speaker, excellent
focus of instruments and voices with proper vertical information and
mid bass fill.
A Genesis loudspeaker system correctly set up, can and should
provide a soundstage that is wall to wall and with pinpoint focus,
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the speakers disappearing completely on a recording containing
such information.
Room Treatment
No room is perfect. To optimize your sonic presentation it may be
helpful to treat your room. Here are some guidelines:
1.
Front walls. This loudspeaker is a dipole and therefore
there is sound coming from both the front and the back of
the speaker. How the front wall is treated or not treated is
important. Generally speaking, the Genesis loudspeakers
prefer a live front wall.
By these terms we mean the amount of reflection of sound.
A typical wall of glass or, brick, cement or drywall material is
a reflective surface. A heavily curtained or sound proofed
wall would be considered a "dead wall" or a non-reflective
wall. A normal thin curtain across a window causes only a
small amount of absorption.
2.
Sidewalls. Because the speaker is a dipole it is less
sensitive to the sidewalls. However, as a rule of thumb, it is
a good idea to keep the speaker as far away from the
sidewalls as is practical. With this in mind, it may be helpful to
add some damping material or diffuser panels to the point of
first reflection. This is a point on the sidewalls between the
listener and the loudspeaker. It is where the sound from the
loudspeaker first hits the sidewall, then bounces to the
listener. This reflection is undesirable because it is slightly
delayed from the original sound. This point on the sidewall
can be easily determined with the help of a second person
and a mirror.
Sitting in your listening position have an assistant hold a
mirror up on the sidewall. Move the mirror until you can see
the tweeter. This is the point of first reflection. A diffuser (see
your dealer), an absorptive material or even a piece of
furniture can help break up this point of first reflection.
3.
Rear wall. In many cases it will be unnecessary to do
anything with the wall behind your listening position.
However, you may want to experiment with diffusers or
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absorbers behind you for best sound. Absorption behind the
listener is usually beneficial.
Mastering the Refinements of the system
Fine tuning an audio system is an art that will take time and
patience. It can be one of the more rewarding learning experiences
you will have in the pursuit of music and its enjoyment.
One of the best pieces of advice we can offer is that you take
advantage of the ear's ability to identify similarities in sound. This
ability is useful in fine tuning your system because if every recording
you listen to has a similarity of sound (too much or too little of a
certain frequency for instance) then you can be fairly certain that you
have yet to perfect your set-up. Keep at it and remember to enjoy
your music as you work on perfecting your set-up.
During the design stage of Genesis loudspeakers, we rely on
hundreds and hundreds of hours of critical listening. There are
changes we can make to the crossover that we can measure, but can
hardly hear the difference. And there are changes that we can easily
hear the difference, but cannot measure. It is an artform as much as a
science! Setting up the audio system is the same.
If you have any questions, feel free to contact us at Genesis. Our
website is the first place that you should look to for more
information, but you are welcome to either send us an email, or just
give us a call!
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The Technology
The Genesis 2.2 loudspeaker comprises four “towers”: two
midrange/tweeter wings and two bass columns. Each tower is over
6 feet tall (183cm), and the cabinet is made of a vibration damping
and resonance-control acrylic/composite sandwich material. The
tweeters and midrange ribbon are mounted on a solid 1.5-inch slab
of high-hardness cast acrylic.
The rationale for the four-tower system separating the woofers from
the midrange/tweeters is to allow the placement of the highfrequency wings to optimize imaging and soundstage, and the
placement of the woofer towers to optimize in-room bass response.
Design Philosophy
Nothing has changed in theoretical acoustics since Lord Rayleigh’s
original book on acoustics published in 1877. There are still only
two proper ways for a transducer to propagate sound in a room: a
point source and a line source. Anything else, or everything in
between, is a compromise.
In order for all frequencies of
sound from the loudspeaker to
reach the listener at exactly the
same time, a coherent wave front
is important - not just “timealignment” of drivers. The ideal is
either an infinitely small pulsating
point or a pulsating line with a size
on the order of the room
dimension.
Obviously, a line-source is much
easier to mechanize than the ideal
John William Strutt Lord Rayleigh (1842 – 1919) point source. The line-source (if
large enough), can approximate
the ideal, and in doing so, provide sufficient radiating area for
dynamically and spatially realistic sound reproduction.
The Genesis 2.2 is a line-source that is 4 feet long (nearly the half
the room’s entire height). A line source has no vertical dispersion at
any frequency. Hence there is no sound bouncing from either the
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floor or the ceiling. No deleterious interference from these surfaces
is created (as in virtually all other kinds of speakers).
Another advantage of the line source is that the vertical spectral
content of music is virtually the same throughout the length of the
line source. Hence, the seating height does not matter with this
speaker; unlike point source speakers where it is important for the
ears to be aligned in relationship with the tweeter.
The Genesis 2.2 is also a dipole radiator. The midrange and
tweeter drivers are mounted on a rigid acrylic panel with no
enclosure. This has two advantages: firstly, it eliminates any
enclosure or boxy colorations caused by cabinet vibrations or
resonance.
Secondly, the dipole creates a cardioid pattern (like a figure-eight),
which has its maximum output at the listening position and behind
the speaker itself, and minimum output to the sides in the plane of
the loudspeakers. This very effectively minimizes the bounce from
the sidewalls.
Hence, in conjunction with the line source, the G2.2 has no first
reflection from the floor, ceiling or sidewalls. The net result is that
there are far fewer detail-robbing room reflections from the room
than other types of loudspeakers. With fewer spurious reflections to
confuse your hearing, the program source emerges more clearly.
Imaging is deeper, yet more focused.
This results in a loudspeaker system that is virtually roomindependent. Also, because there are no phase and frequency
distorting reflections created, one can be transported into the
audience of the actual concert hall where the music was recorded.
The Genesis Ribbon Tweeter
Reviewers in the Audiophile press have often remarked that the
Genesis circular ribbon tweeter is the world’s best. It is a one inch
circular planar ribbon design crafted from an extremely thin
membrane of Kapton with a photo-etched aluminium “voice coil”
that is a mere 0.0005 inch thick. The entire radiating structure has
less mass than the air in front of it! That is why it will accurately
reproduce frequencies to 36 kHz.
The result of this design is a driver that has a rapid and uniform
response to high frequencies, and has the speed of the best
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ribbon/electrostatic designs without the high distortion and poor
dispersion that is typically associated with them.
The G2.2 uses twelve of these tweeters configured as a vertical
line source. Because the output is distributed over many drivers,
each works at very low-stress. This dramatically lowers the
distortions in the high frequencies.
The G2.2 also use three rear-firing tweeters per channel wired to
the crossover out of phase to the front tweeters creating a dipole.
48inch midrange ribbon
We sometimes say that the midrange is a window into the mind of
a composer or a singer. And indeed, the midrange is where the
“magic” is in a well-recorded musical event. This is why the G2.2
loudspeaker system uses a single 48inch-long ribbon per channel
as a dipolar line-source to reproduce these critical frequencies.
The midrange ribbon used in the G2.2 is manufactured to Genesis’
exacting specifications. The ribbon itself is made of a very thin layer
of aluminium laminated to a substrate of mylar that is 0.001inch
thick. The ribbon is then suspended in the magnetic field created
by over 24 feet of barium ferrite magnets.
This results in a perfect line-source ribbon generating a continuous
and perfectly coupled wave front. The benefit of this to the listener
is a wide and even horizontal dispersion yielding a large and highly
stable sweet spot.
As a line-source dipole, the midrange ribbon has a vertical
dispersion pattern identical to that of the line array of tweeters.
Thus further insulating the listener from the room’s negative effects,
and enhancing the sense of spaciousness and depth.
The Servo-bass Advantage
Very few loudspeakers use servo drive, either because most
designers think that it is too difficult to design, too expensive, or
because of the extraordinary demands a servo system makes on
the amplifier and the transducer. The history of the Genesis servosystem started from the first introduced in the legendary Infinity
Servo Statik One in 1968(!) – so we know how to design and build
servo systems. The technology has been constantly updated and
refined over the past 40 years.
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The concept of our servo bass system is an easy one to
understand: It employs an accelerometer as a sensor to constantly
monitor the movement of the woofer cone and continuously
compares it to the input signal. This comparison circuit instantly
identifies any deviation from the input and applies a corrective
signal to compensate for any deviation, resulting in the virtual
elimination of the inherent distortion of the woofer.
As an example, when you have a high-impact, low-bass signal that
starts and stops suddenly (for example a tympani), the inertia of the
woofer cone makes it slow to start moving, and then after it has
started moving, the momentum of the cone makes it continue to
move after the signal has stopped. The sonic result is softness,
overhang, and bloat in the bass. This results in a perceived lack of
tautness and definition, and a blurring of dynamic impact.
With the servo system, the circuit senses that the woofer is not
moving as fast as it should, and it instantaneously applies much
more current to make it move faster. When the signal stops, it
predicts that the woofer will continue to move when it shouldn’t be
moving and applies a counter-signal to stop the woofer faster and
more effectively than an open loop woofer could possibly respond.
Thus, the servo-drive reduces distortion and improves transient
response by making the woofer appear to be massless. Typical
non-servo woofer systems have distortion levels that exceed 10%
at even moderate levels. The Genesis servo bass system reduces
this distortion to below one percent at almost any output level. The
system also drives the woofer to constant acceleration, which
makes the frequency response of the woofer anechoically flat to
the lowest frequencies.
The Woofer Tower
The transducer used in a servo system must be strong enough to
withstand the high current approach of the servo, and yet delicate
and light enough to react extremely quickly. The G2.2 features a
total of four front- and four rear-firing 8-inch woofers per channel –
a total of sixteen woofers in the system.
While the servo system is able to ensure that the driver works
linearly as a perfect piston, it is unable to correct for distortion
caused by cone wobble, bending, and break-up. Hence, the drivers
were designed to minimize these non-linear distortions.
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absolute fidelity
The woofers are a uniquely designed metal cone driver made for
the Genesis servo system. Made with a cone of solid aluminium,
the suspension and voicecoil have been maximized for long
distortion-free excursion so as to increase dynamic range. Our
aluminium cones are a magnitude stiffer than any plastic cone on
the market, and virtually eliminate the problems caused by cone
bending and break-up.
The lowest break-up mode (where there can be any chance of
distortion at all) is at 6,000Hz – far above the 16Hz to 120Hz
frequency range that these drivers operate at. Therefore, the driver
is a perfect piston within the frequencies used. Thus, extremely low
cone break-up distortion is inherent in the driver that is designed for
the Genesis 2.2.
Unlike the midrange and the tweeters, the front and rear woofers
operate in phase as a bipolar arrangement in which all sixteen
operate in unison to control the air mass of the entire room. This
means that the surface area of the eight cones and the large
enclosure all work together in unison to produce bass output that
descends evenly to below your hearing limits.
Servo-controlled Amplifier
One problem, however, of metal cones, is that of greater mass
(even ones as light as the ones used in the G2.2). To over come
this, Genesis had to build an amplification system of great power,
and high damping factor. The servo system also places
extraordinary demands on the amplifier because the system uses
enormous amounts of current to make the woofer follow the input
signal. Combined with the metal cones, this means that the
amplifier used must efficiently deliver extraordinarily large amounts
of clean power into very low impedances.
In the Genesis 2.2, the amplifier was designed as a holistic system
of woofers, integrated connecting cables, amplifiers, servo-control
and remote controlled crossover circuitry. Two separate twochannel amplifier modules are used for the left and right woofer
towers.
Specially designed and tuned “Dynamic Reserve” power supplies
are used – one for two channels – to deliver balanced dynamics
which are critical to bass accuracy. This improves the power factor
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of the power supply in delivering the bass frequencies, resulting in
“floorshakingly musical” bass to power the servo woofers.
A further advantage to separating the amplifier modules of the left
and right woofer towers is that if you are lucky enough to have
multiple 20amp circuits in your listening room, you can power each
woofer tower with a separate circuit! This allows for even better
transient bass dynamics. The Dynamic Reservoir (from the
Genesis Reference Amplifier) can also be adopted for the ServoControlled Bass Amplifier, which will give even faster bass
transients.
One side benefit of this powered woofer system is that almost any
sized amplifier can be used to drive the mid/tweeter section of the
Genesis 2.2. No longer must one choose between having an
amplifier with enough power to drive the woofers, and a smaller
amplifier having better spatial and tonal characters. Nevertheless,
we do recommend no less than 100 watts as a minimum for the
mid/tweeter sections.
The Acoustic Suspension
The suspension for each loudspeaker tower comprises three
elements:
1)
The neoprene vibration absorbers are tuned to isolate and
decouple the loudspeaker cabinet for optimal imaging and
bass response no matter what surface the loudspeaker sits
on.
2)
The skeletal frame acts as a tuned absorber. Made of an
inch of solid acrylic, no two parts of the frame will resonate at
the same frequencies. This ensures that all midrange
frequencies are “dumped” below the base of the cabinet so
that floor-borne vibrations do not affect the imaging and
soundstage of the loudspeaker.
3)
The spikes rigidly couple the suspension system to the floor.
If you have hardwood floors and do not want to make holes
in the wood, use a copper penny (instead of expensive
“spike cups”) under the spike.
A pin-point suspension system is designed to pass all
frequencies. Using a spike cup under the spike will defeat
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this system. The spike passes all frequencies to the spike
cup, and then depending on the diameter of the spike cup, it
passes only frequencies below a particular frequency.
A copper penny gets deformed – the spike making an
indentation where it meets the penny, and a little “nipple” on
the other side. This still performs the same function as a pinpoint suspension system, but at the same time protects your
hardwood floor.
Nevertheless, despite the acoustic suspension, if you have a
extremely light and resonant floorboards, the acoustic suspension
may still transmit sufficient vibrations to make your floor resonate
and hence muddy up the bass and the imaging. In that case, it may
be necessary to place heavy marble, slate, or granite slabs (at
least 100lbs per slab) under the speakers. This slab serves as a
foundation on which the acoustic suspension will work.
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Specifications
Dimensions:
Mid/Tweeter Wing:
Woofer Tower:
Amplifier (stack):
Power Supply:
H 75” x W 21” x D 16”
H 75” x W 15” x D 26”
H 11” x W 17” x D13”
H 6” x W 10” x D 12”
Weight:
720 lbs (328kg) wing/towers
90 lbs (41kg) amplifier total
Frequency Response:
16Hz to 36kHz, +/- 2dB
Controls (on amplifier):
Bass volume, phase,
low-pass, high-pass
Controls (on speaker):
Rear Tweeters (+/- 1 dB)
Midrange (+/- 0.75 dB)
Input Impedance:
4 ohms (nominal)
33K ohms (amplifier)
Sensitivity:
91 dB 1 watt 1 meter
Amplifier Power Rating:
4 channels @500 watts each
Power Supply 1kVA per side
Amplifier Inputs:
1pair XLR (balanced)
Finish:
Acrylic composite
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